Experimental Hydro-uteri (Hydrometra) in Rodents and Some Factors Determining Their Formation. ∗

Abstract

In mice of the English Silver Strain, and occasionally in other strains there occurs a condition of imperforate vagina which leads to a marked distention of uteri with accumulation of fluid up to 15 ml or more per mouse. Yet normal function of the uterus is preserved, since such animals become pregnant if the membrane occluding the vagina is removed(1). Existence of huge hydro-uteri in the presence of imperforate vaginas suggested that simple ligation of the cervix in rodents might likewise induce formation of hydro-uteri. This new technic not only provides a large uterine receptacle for tumor transplants but also permits the collection of large amounts of uterine secretions in small animals.

This paper reports studies on production of hydro-uteri in mice, rats and hamsters and on hormonal and other factors which play a role in development of experimental hydrouterus.

Methods. The cervix of the uterus was ligated under nembutal anesthesia through a supra-pubic incision in 456 mice, in a smaller number of rats (Wistar) and Syrian hamsters. The variables for this study of effects on development of hydro-uteri were strain of mouse, endocrine status and time elapsing between uterine cervix ligation and autopsy. The strains 0.f mice and types of animals used are shown in Tables I and 11. Eighty-four mature white Swiss mice, 40 DBA/1 and 40 C57BL/lOJ mice were castrated and their cervices ligated (Table I). Forty-seven immature intact white Swiss mice underwent cervical ligation. One to 2 weeks later, castrates received injections subcutaneously as follows: controls, 0.5 ml sesame oil: estrogen treated animals, 1 γ estradiol daily; testosterone treated animals, 0.1 mg testosterone propionate every other day for 12 days. Twelve days later these animals were sacrificed. The effect oi length of time after ligation of the cervix was studied in mature intact animals by periorming exploratory laparotomies at varying interyals (up to 12 months) after cervical ligation.